混凝土斜拉桥施工控制的最佳成桥状态法

根据现代斜拉桥结构设计理论的悬臂施工方法的特点，提出了以最佳成桥状态作为施工控制的最终目标，以实施最佳施工阶段为技术路线，以索力调整为核心内容的斜拉桥施工控制理论，简称为最佳成桥状态法；以斜拉桥主梁标高误差最小为目标函数，以主梁内力（弯矩）为约束条件，以索力为优化变量，建立了最佳施工阶段的索力调整计算模型；推导了考虑徐变收缩效应的索力调整计算公式；用最佳成桥状态法对一实桥工程进行了施工控制全过程计

AN OPTIMUM COMPLETION STATE METHODFOR THE CONSTRUCTION CONTROLOF RC CABLE-STAYED BRIDGES

According to the design theory of the cable-stayed bridge and to the feature of thecantilever construction the authors propose a construction control method called Optimumcompletion State Method(OCSM) for RC cable-stayed bridges. In the proposed method, theoptimum completion state is regarded as the final target of the construction control, and theoptimum construction state at each construction stage is taken as the technical route. The key ofthe method is to properly choose or adjust the cable forces. The objectives function of optimizationis to minimize the elevation error of the girder under the constraint condition that the internalforces(bending moments) of the girder are bounded. The optimization variables are the cableforces On the basis of the above principles, a optimum model for a construction step isestablished and cable force adjustments can be found for each construction step. In this model, theor&p and shrinkage effects of concrete have been considered. A bridge example is given whichshows that the final state of the bridge is very close to the design aim and that this method ismuch better than the so-called double-control method. The example is a good illustration of thesoundness and practical value of the proposed method.